There have been 15 federal court judges impeached. Only one, Samuel Chase,
Associate Justice, was a member of the Supreme Court of the United States.
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http://www.fjc.gov/history/home.nsf/page/judges_impeachments.html
Samuel Chase, Associate Justice, Supreme Court of the United States. Impeached
by the U.S. House of Representatives on March 12, 1804, on charges of arbitrary
and oppressive conduct of trials; Acquitted by the U.S. Senate on March 1, 1805.
And one of them, Alcee Hastings, has been a sitting Congressman for 22 years.